Semithreadless drill stem



Dec. 31, 1940. A. BOYNTON SEMITHREADLESS DRILL STEM Filed Sept. 22, 1938 l l I J Patented Dec. 31, 1940 UNITED STATES PATENT OFFICE 4 Claims.

My invention relates primarily to improvements in drill pipe for wells drilled by the rotary method and other pipe and, particularly, to means for connecting the joints thereof together.

The principal objects are: (1) To provide a means for connecting the joints together so that the'drill stem can be-rotated either clockwise or anti-clockwise without danger of the joints becoming disconnected, (2) to relieve the threads or circular keys, employed in place of threads, of torque caused by rotation of the drill pipe, (3) to eliminate the compression strain upon the male member and the expansion strain upon the female member of the connection while drilling,

(4) to provide mechanism to take the rotation torque separate from the mechanism which holds the joints together, (5) to prevent the threads or keys, employed in place of threads, from galling, (6) to prevent leakage between the male and female member of the connection, and, (7)

by the employment of small force in making and breaking the connections, to afford greater safety for drilling crews than can be provided by the preset threaded means for connecting drill pipe. A socket wrench-line contact between the end of the drill pipe and the shell or coupling member permits rotation of the drill pipe in either direction, absorbs all the rotary torque, avoids the compression strain upon the pipe and the expansion strain upon the coupling, and imposes upon the threads or keys, employed in place of threads, the one duty only of holding the pipe together while itis being inserted into or being withdrawn from the well. a I attain the foregoing objects by mechanism illustrated in the accompanying drawing in which- Fig. l is alongitudinal section thruthe preferred embodiment of the invention. Fig. 2 is a cross section on the line 2-2, Fig. 1. Fig. 3 is a cross section on the line 3-3, Fig. 1. Fig. 4 is a longitudinal section thru a modified form of this invention. a X a I Fig. 5 is a cross section on the line 5-5, Fig. 4. Fig. 6 is a cross section on the line 66, Fig. 4. Similar characters of reference refer to similar parts throughout the several views of each pipe enmesh with the lands 2a ofthe couplingshell, as clearly appears in Fig. 3. The U-cup 6,

which may be of leather or any other tough, ex-

pansible substance, isiltted within an internal I recess within the coupling-shell 2 somewhat 5 above the slots Ibof the drill pipe. This cup,

which may besubstituted by V-packingor the like, is adapted to be expanded by fluid pressure from below it. If any pump fluidshould attempt to escape thru the slight annular clearance be- 10 tween the drill pipe and coupling-shelLthis cup will seal off between the members I and 2; thereby providing a leak proof connection, as appears inFig.l. f

To assemble the parts to formthe connection, 15

as shown in Fig. 1, the drill pipe I is seated upon the circular shoulder' lb." If,beforecso-seating,

the drill pipe should cometo rest upon the lands 2a of the couplingshell, slight rotation of the pipe will cause the lands Ia and 2a to enmesh. 20 The two halves of the securing ring 3, having annular lands or projections 3a, adapted toengage between similar projections 2d within the coupling-shell, are then dropped into the annular space between members I and 2, landing upon 25 the annular external shoulder Id of the" drill pipe. The two halves of thespreader ring 4, having their lower ends externally beveled at 4c, are then inserted between the halves of ring 3 and the drill pipe, forcing the two halves of ring 3 30 outward and causingits annular projections Ia to enmesh with the similar projections 2d within the coupling-shell 2. The ring shaped head 4a of ring halves I then engages upon the upper end of ring halves I. The snap or look ring 5 35 is then inserted, engaging between the head la and the internal bevel 2c of the coupling-shell. This *completesthe assembly. The openings 3b between the halves of ring 3, theopenings lo, I between the halves of ring I, andthe opening 5a 40 in the snap ring 5, are for the evident purpose of enabling the assembly of these parts to be made. I

The enmeshed lands Ia and 2a of the drill pipe and coupling-shell, respectively, will not permit 45 rotation oisaid membersiindependent or each other (see Fig. 3). The enmeshed projections 30 and 2d secure the pipe and coupling-shell together against being pulled, apart because the shoulder Id is engaged under the ring 3 and the 6 ring 4 is engaged under the snap ring 5. It, therefore, is apparent that the assemblyshown in Fig. 1 may be rotated either clockwise or anticlockwise without danger of the joint becoming disconnected and that the drill pipe will be it pulled out of the coupling-shell, provided, of

course, that the enmeshed relation between the members 2 and 3 is made of proper length and that the projections 3a and 2d are of proper size. For 4 drill pipe, for example, a. satisfactory connection can be made by providing a length of three inches for the member 3 and making the enmeshed projections 3a and 2d by 3 9".

The snap ring 5 may be quickly and easily removed by compressing it to partially close the opening 5a between its ends; whereupon the ring 4 may be lifted out and the ring 3 moved inward against the drill pipe and also lifted out. The drill pipe may then be removed from the cou pling-shell, as is plain to be seen in Fig. 1.

Figs. 4, 5, and 6 illustrate the modified form of this invention.

In Fig. 4 the lower joint of drill pipe IA may be threadedly joined and welded to the couplingshell 2A, as in Fig. 1. The upper joint of drill pipe IA is closely slidable within the couplingshell 2A and has its lower end landed upon the internal circular shoulder 2Ab while its lands IAa are enmeshed with the lands 2Aa of the member 2, as appears in Fig. 6. The U-cut 6A, positioned in a recess within the coupling-shell slightly above the cut lAc, prevents leakage of pump fluid between the members IA and 2A, as was stated for the similar cup 6 in connection with Fig. 1. v

To form the connection, as in Fig. 4, the drill pipe is landed upon the internal shoulder 2Ab and the amembling nipple I, split in two halves, as shown at opening Ia, conforming to the drill pipe and having threaded connection within the upper end of the coupling-shell 2A, is screwed down firmly upon the external shoulder IA!) of the drill pipe. The square spring wires 8, having their ends slightly apart at 8a, are formed to'the circle of the grooves in nipple E into which grooves they are fitted, hold together the halves. of nipple I so that it'will remain upon the drill pipe when the latter is withdrawn from the coupling-shell and so that the threads will remain in line for quick and convenient engagement with their mating threads when the connection is tobe remade. I

All pulling part strain upon the drill pipe is borne upon the shoulder lAb engaging with the lower end of split nipple I, as is apparent. The threads will not gall because the rotary thrust of the drill stem is borne by the enmeshed lands lAa and 2Aa which permit the drill stem to be rotated in either direction without danger of becoming thereby disconnected. For the same reason the threads will not be screwed together more tightly when the drill stem is rotated in drilling. Thus is eliminated the great force and resulting danger of making up and breaking out drill pipe connected by threads which must be made up tightly to support the weight oi the drill stem while it is being inserted into the well and which make, up much tighter during the operation of drilling.

Preferably, a connection such as shown in Fig. l or 4 should be employed to form all connections in the drill stem, thus avoiding the use of tool joints and accomplishing all of thestated ob jects.

Obviously, either form of this invention can be employed for pipe unions or means for connect pulled apart between the joints before it will be ing shafts together, and other similar or related.

. purposes.

Where the word pipe is employed in the claimsv herein, it is therefore intended that shafts, rods, stalls and the like are included. Where the construction shown in Fig. 1 is employed for pipe unions, the enmeshed land la and 2a of the pipe and coupling-shell, respectively, may be omitted and packing may be placed under the split ring 4, the bevel 4c serving to compress the packing. Where the construction'shown in Fig. 4 is employed for unions the enmeshed lands lAa of the pipe and 2Aa oi the coupling-shell may be omitted. Packing may also be placed under the lower end of ring I.

It is apparent that many minor changes in con struction and substitution of parts may be made within the scope and purpose of the objects stated and claims appended, and I reserve the right to make such changes and substitutions.

I claim:

1. A pipe connection including non-rotatably interfitting pipe ends, a shoulder outstanding on the periphery of the internal pipe end, and means fitted into the external pipe end after interfitting of the pipe ends to engage said shoulder and hold said ends against axial movement, saidmeans including a split ring, movable radially outward to fit said external end, a spreader ring to hold said split ring, and a snap ring to lock said spreader ring. I

2. A pipe connection including n'on-rotatably interfltting pipe ends, a shoulder outstanding on the periphery of the internal pipe end, and means fitted into the external pipe end after interfitting of the pipe ends to engage said shoulder and hold said ends against axial movement, said means including a split ring threaded into said external ring, and a lock ring therefor.

3. A drill pipe connection including a pipe section, a shell member fixed thereto, a pipe end non-rotatably interfitting said shell, a shoulder on said end, a shoulder in said shell, a grooved area above said shell shoulder, a retainer ring to drop into-said shell to seat on said shoulders,

ribs on the periphery of said retainer ring to fit said grooves, a spreader ring to fit inside of said retainer ring and move said ribs into said grooves, and}. snap ring to lock said spreader ring in said shell],

4. In a pipe connection, a pipe slidably received within a coupling shell and having its end landed upon a circular shoulder therein, said shell and the end of said pipe being interfittingly locked together by enmeshed lands; an annular recess around said pipe forming a shoulder thereon within said shell, a second recess within said shell, said last recess being opposite the first and having annular projections, a. transversely segmented ring in said second recess, said ring hav tudinal movement between said pipe and shell, 70

and means for preventing leakage last members.

ALEXANDER BOYNTON.

between" said 

